A SOPHISTICATED ‘bullet beater’ that was introduced to crackdown on inner city gun gangs in Birmingham has been ditched after it failed to pick up four confirmed shootings in the last 12 months.

Details of the Shotspotter system’s failings were revealed last month by police chiefs who told a Handsworth community meeting that it would have cost at least £40,000 per year to monitor in the future.

The Birmingham Community Safety Partnership - which funded the system - decided to pull the plug because of issues over accuracy and cost.

The system was introduced in December 2010, but initially struggled in Birmingham – which is the only UK city to be piloting it – because of the low number of shootings and the illegally converted weapons typically used by gangsters.

A spokesman for the force said: “We’ve always said technology alone won’t stop gun crime and this technology is not necessarily reducing gun crime.

“It’s no secret there’s been technical difficulties so we’ve decided not to carry on.

“We’ve always said it’s a pilot and we’ve just decided not to carry on with it.”

The cost of operating the system was also part of the decision to take the sensors down, he added.

The devices were placed high up on buildings covered by the West and Central local policing unit, which includes Handsworth, Aston and Newtown.

Audio sensors were meant to detect a gunshot and send its location, in an alert, to police officers.

Shotspotter, which is used in 50 cities across America, uses a network of microphone sensors grouped in crime hotspots to pinpoint gunfire to within 25 metres.

The sensors were recalibrated in November and experts in the US have been providing 24-hour analysis of any alerts.

Councillor Waseem Zaffar (Lab, Lozells and East Handsworth) said: “I was originally very supportive of this and I was keen to try and use technology to tackle this problem.

“But in January and again last month I voiced my concerns about the accuracy. It was clearly not working as well as in America.

“There is no point having a system that is nowhere near good enough. We were promised 85 per cent accuracy and we got nowhere near that.

“I think it was a wise decision to cut our losses and move on by using the resources to tackle the problem in other ways.”

In August, Chief Superintendent Clive Burgess told residents, community groups and politicians that the system had received 1,608 alerts since the November restart.

He added that only 45 alerts were passed on as possible shootings from the US experts to the force control centre. He added that 33 of those were either fireworks or gunshots.

A further 10 were classified as a single gunshot sound, but only two were confirmed as firearm incidents – including one which involved multiple firearms.

It failed to pick up four other confirmed incidents in the areas it was located in.